More From Sectornomics: Technology

Tech giants like Google, Apple and Samsung may seem eternal at the moment, but technology is an industry in which a slide from the top is all but inevitable. Leaders come and go regularly—and today's tech giants can become a mere shadow of themselves in quick fashion.

These breakdowns aren't necessarily fatal. The companies who have them may survive and even continue to be profitable. But they cede the cachet they once had as king of their hill to a competitor who was either more nimble or had better insight into the way the industry was evolving.

Here's a look at 10 companies who once commanded their industries but have since fallen from the top spot.